Google claims their users click (organic) search results more often than ads, essentially rebutting the research cited above. A 2012 Google study found that 81% of ad impressions and 66% of ad clicks happen when there is no associated organic search result on the first page. Research has shown that searchers may have a bias against ads, unless the ads are relevant to the searcher's need or intent 
Traffic from organic search is free and long-lasting, which makes you less dependent on advertising budgets. If you look at the list of the top three American e-commerce retailers, you will find that it matches the above data with the top three companies getting the most organic traffic. This definitely proves that SEO pays off in the long run: you attract quality traffic in large volumes without paying for it directly.
If the blog post you’ve selected has less than 2,000 words, one simple way to increase organic traffic is to increase the word count — but don’t just fluff it up. Make sure any content you add also adds value. Instead of watering down paragraphs, add completely new sections that cover points you haven’t introduced yet. Chances are, the added word count will allow you add additional keywords. Speaking of…
Let’s say you wish to block all URLs that have the PDF. extension. If you write in your robots.txt a line that looks like this: User-agent: Googlebot Disallow: /*.pdf$. The sign “$” from the end basically tells bots that only URLs ending in PDF shouldn’t be crawled while any other URL containing “PDF” should be. I know it might sound complicated, yet the moral of this story is that a simple misused symbol can break your marketing strategy along with your organic traffic. Below you can find a list with the correct robotx.txt wildcard matches and, as long as you keep count of it, you should be on the safe side of website’s traffic.
I had great results with Stumble Upon cause I have been a user for years and Stumble a lot of things that have nothing to do with blogging or my blog. And Networked blogs is working great for me too :) I am glad you found some new sources here. I would love, if you had the time, to look into one or two that seam interesting to you, and maybe try them out... and then come back and tell me if they worked OK for you?
Organic is what people are looking for; the rest of these simply put things in front of people who may or may not be seeking what you offer. We know that approximately X number of people are looking for Y every day. So if we can get on front of those people, we have a much greater opportunity to create long-term relationships and increase our overall ROI.
This is the number of views that you can test each month on your website.It's up to you how you choose to use them, either by allocating all the views to one test or to multiple test, either on one page or on multiple pages. If you have selected the 10.000 tested views plan and you run an experiment on your category page which is viewed 7000 times per month, then at the end of the month 7000 is what you'll be counted as tested views quota.